{"product_id":"honeywell-621-9938r-serial-i-o-module","title":"Honeywell 621-9938R Serial I\/O Module","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThe Honeywell 621-9938R is a Serial I\/O Module (SIOM) used in Universal Control Network (UCN) systems. It manages communication between remote I\/O card files and the processor card file via serial links. Designed for redundant and nonredundant configurations, it ensures reliable data exchange in distributed control environments.\u003c\/p\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCommunication Protocols:\u003c\/strong\u003e RS-232, RS-485, optional CAN (in some configurations)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVoltage Input:\u003c\/strong\u003e 24 VDC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCurrent Consumption:\u003c\/strong\u003e ~300 mA\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions:\u003c\/strong\u003e 1.5\" × 10.5\" × 6.5\" (3.8 × 26.7 × 16.5 cm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.7 kg\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCertifications:\u003c\/strong\u003e CE, FCC compliant\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI\/O Capacity:\u003c\/strong\u003e Supports 8, 16, or 32-point configurations\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRedundancy Support:\u003c\/strong\u003e Dual communication ports for redundant serial links; interfaces with model 621-9939 SLM\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDIP Switch Configuration:\u003c\/strong\u003e\n\u003cul\u003e\n\u003cli\u003eSW1: Starting address (0–2032, increments of 8)\u003c\/li\u003e\n\u003cli\u003eSW2: Fault response and test mode\u003c\/li\u003e\n\u003cli\u003eSW3–SW5: I\/O points per slot\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTermination Requirements:\u003c\/strong\u003e 200 or 300 Ω resistors at each end of the serial channel; required in SIOMs at the extreme ends\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eInstallation Notes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eInstall in slot N of the remote serial I\/O card file\u003c\/li\u003e\n\u003cli\u003eEnsure proper DIP switch settings to avoid address overlap\u003c\/li\u003e\n\u003cli\u003eUse Serial Link Selector (621-9928R) for dynamic link switching to active processor\u003c\/li\u003e\n\u003cli\u003eAvoid installing 8\/16-point modules in 32-point slots\u003c\/li\u003e\n\u003cli\u003eMaintain cable impedance matching with terminating resistors\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Honeywell","offers":[{"title":"Default Title","offer_id":42547171229763,"sku":"621-9938R","price":66.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0587\/5810\/3107\/files\/621-9938R_2.png?v=1756365856","url":"https:\/\/www.plcdcspro.com\/products\/honeywell-621-9938r-serial-i-o-module","provider":"PLC DCS Pro Ltd.","version":"1.0","type":"link"}